Well screen



June 10, 1952 G. F. ABENDROTH WELL SCREEN Filed Nov. 9, 1950 lef 132 INVENTOR. Guss F. Abendroh F16. 5.

ATTORNEY.

Patented June 10, 1952 urlrrsp .STATES PATENT OFFICE Guss F. Abendroth, Houston, Tex., assigner, by Y mesne assignments, to Standard OlDevelepment -Cmpany, Elizabeth, J., a corporation of Delaware Application November 9, 1950.Seri`a1`No. 194,743

4 Claims. l This invention relates to a well screen and, more particularly, relates to a screen used in conjunction with producing iiuds from incompetent subsurface .formations In producing fluids, vparticularly oil and gas, from subsurface formations, much dili'culty has been encountered in those instances in which subsurface strata penetrated :by the borehole are incompetent. When liuid is produced from such a formation, very fine sand becomes entrained in the formation iluids and is produced along with the fluids. In some elds the quantity of entrained formation materials is so large that the fluid cannot -be economically produced, a fact which may result in abandonment of the well.

In combatting the difliculties arising from the presence of unconsolidated materials, various practices have been adopted. For example, it is common practice to employ crude screens such as a section of slotted pipe, perforated pipe and wire-wrapped screen. Screens prepacked with gravel have also been used. ln particularly troublesome cases, sections of the borehole surrounded by incompetent formations have lbeen packed with gravel. Unfortunately all of the devices heretofore used are subject to erosion by the entrained formation materials and are subject to being clogged by such materials, thereby' seriously reducing the amount of fluid which can now therethrough. Furthermore, Vsome of these devices are fragile and, consequently, are easily broken at the time they are installed or later when in use.

An object or the present invention is to provide an oil well screen which is rugged and simple. A further object is to provide an oil well screen cf such a design as to materially reduce erosion due to entrained formation materials. A further ob-ject is to provide a screen which can be maintained in service for long periods of time without clogging.

rI'he present invention may be described briefly as a borehole screen for Wells producing fluids, particularly oil and gas, which includes an inner cylindrical permeable nlter sleeve composed of sintered metal. Surrounding this sleeve concentrically is a tubular member equipped on its inner surface with inwardly extending projections which contact the sleeve, giving the sleeve support. These projections also space the sleeve away from the inner surface of the tubular meinber and are so arranged as to permit the huid to flow longitudinally within the space between the outer surface of the sleeve and the interior surface of the tubular member. The upper end of the Icylindrical sleeve may be closed by means of a vsolid plate o1" by means of a cover made of permeable sintered 'metal in which case it is backed up by a metallic plate extending transversely across the tubular member, this plate being provided with downwardly extending proiections to support the sintered metal screen and to permit fluid to flow laterally between the screen and the plate. The lower lend of the screen may be closed olf by means of a plate or it may be allowed to remain open, but the annular space between the outer surface of the sleeve and the inner surface of the surrounding tubular member is closed off at the lower end of the sleeve. Transversely extending conduits may be Iprovided which extend from the tubular member into the interior of the sleeve. The interior of the sleeve is lled with a nely divided aggregate material, such as sand, the aggregate material being consolidated with a suitable binding material, such as plastic, to form a solid, permeable mass through which fluids Gan flOW.

When such a device is lowered into a borehole and positioned opposite a producing formation, the well fluids flow from the well bore through the open lower end of the iilter sleeve or through the transversely extending conduits into vthe interio'r of the screen and then through the permeable sleeve into the space between the outer surface of the sleeve and the inner surface of the tubular member. It 'will be apparent that the fluid entering the well screen must pass through the sand disposed in the interior of the well screen before it reaches the screen. Furthermore, the sand tends to spread the fluid `over a large surface ofv the filter sleeve. This arrangement prevents the formation materials from clogging the filter sleeve and, accordingly, the screen has a long', useful life. l'nasmuch as the sintered metal filter screen is supported on the inside .by the consolidatedv sand and on the outside by the aforementioned inwardly extending projections, it can withstand both burst and collapsed pressures and, accordingly, is not subject to breakage when in use in a producing string.

The present invention will be more fully understcod from the following detailed description of typical preferred forms of my invention through out which description reference is lnadevto the accompanying drawings, in which:

Fig. 1 is a longitudinal cross-sectional view of one embodiment of the well screen of my invention;

Fig. 2 is a cross-sectional view of a modincation of' a portion of the device shown in Fis. l;

Fig. 3 is a modification of a portion of the device shown in Fig. 1.

Fig. 4 is a longitudinal cross-sectional View of another embodiment of the well screen of my invention; and

Fig. 5 is a detailed showing of the spacing means between the screen and the outer tubular member of Fig. 4.

Referring to Fig. 1, I designates a cylindrical permeable filtering sleeve composed of sintered metal. In constructing this screen any metal may be used which is capable of resisting corrosion of well fluids, and stainless steel is particularly suitable for this purpose. An end wall also composed of sintered metal is aixed to the upper end I2 of sleeve I0. Surrounding sleeve I8 is tubular member I3 having grids Hlmachined on the inner surface thereof. In Fig. 1 grids I4 are shown as circumferentially arranged in longitudinally extending rows. Projections I4 contact the outer surface I5 of sleeve I9, thereby physically supporting said sleeve. A transversely extending plate 'S is disposed above end wall |I of sleeve IB and is aixed to tubular member I3 as by means of welding the outer periphery of plate I6 to projections I4 as indicated at 9. Plate I6 carries on its under side II a plurality of downwardly extending projections I8, these projections abutting against the outer surface I9 of end wall II, giving it support. The lower end 2B of sleeve IB and the lower end 2| of tubular member I3 are closed by means of closure plate 23 although it is obvious that plate 23 need not close the lower end of sleeve I0.

A plurality of conduits 24 extend from tubular member I3 into the interior of sleeve I0. The` particular number of conduits employed and their spacing with respect to each other is not critical, the only requirement being that means be provided for permitting formation fluids to have easy access to the interior of sleeve Il). In the drawing, conduits 24 are shown as circumferentially and longitudinally spaced along tubular member I3. The space confined within sleeve I0 between end II and closure plate 23 will hereinafter be referred to as the inner chamber. This inner chamber is filled with a highly permeable, finely divided aggregate, such as a highly permeable sand, which is consolidated with a suitable material, such as a plastic, to form a solid, permeable mass within said chamber. Since the sand is placed inside and consolidated in the inner chamber subsequent to the time that conduits 24 are installed, it is convenient to permit the consolidated sand to also fill conduits 24 ush with the outer surface 25 of casing I3.

Although the distance which conduits 24 extend into the inner chamber is not critical, it is desirable that these conduits extend a considerable distance into the chamber and preferably should be allowed to extend approximately to the axial center thereof. By so doing, the path which the incoming oil must take through the sand before reaching sleeve III is increased to the maximum.

As is shown in Fig. 1, the upper end of tubular member I3 may be swaged down and provided with a threaded end 26 so as to be easily attachable to ,a section of pipe.

Instead of inwardly extending projections I4 being in the form of grids shown in Fig. l, projections I4 may be in any other form which will permit fluid to flow longitudinally in the space between the outer surface I5 of sleeve II) and the inner surface 2l of tubular member I3.

In the embodiment shown in Fig. 2, tubular member I3 is shown as having a plurality of circircumferentially spaced longitudinally extending projections I4. The inner surface of these projections abut against the outer surface I5 of sleeve I0 while permitting fluid to move longitudinally in the spaces therebetween.

Rather than having an end wall II of sintered metal afxed to the upper end I2 of sleeve IG, upper end I2 may be closed by a metal plate 28 affixed to tubular member I3 by suitable means such as welds 8 as is shown in Fig. 3. It will be appreciated, of course, that spaces 29 must be allowed to remain around the edge of plate 28 `so that fluid can pass from the space between the outer surface I5 of sleeve III and the inner surface 21 of tubular member I3 into the space 30 above sleeve I0.

When the hereinbefore described screen shown in Figs. 1 to 3, inclusive, is in position in the borehole of a producing well, formation fluid enters the screen through conduits 24 as indicated by the arrows and passes through the permeable, consolidated sand located in the inner chamber through sleeve I0 and end plate II. That portion which passes through sleeve I0 enters the space between the outer surface I5 of sleeve I0 and the inner surface 21 of tubular member I3 and moves upwardly in said space into the space 30 above transverse plate I6. That portion which passes through end II flows into the space between the outer surface I9 of end I I and the inner surface of plate IB, moving laterally within said space and around the edge of plate I6 into the space 30 above said plate. Of course, the uid in space 3!) has been freed of suspended formation materials in its movement through the screen.

Figs. 4 and 5 illustrate another embodiment of the present invention which employs a somewhat different spacing means for spacing the lter sleeve from the inner surface of the tubular member than is shown in Figs. 1 to 3. Referring to Figs. 4 and 5, ||0 designates a cylindrical, permeable filtering sleeve composed of sintered metal. Surrounding sleeve I|0 is a tubular member III, the inner surface ||2 of tubular member III being spaced from the outer surface I|3 of lter sleeve ||0 to dene annular space ||4 between said members. Disposed in annular space ||4 is a spacing and supporting member 5 which may consist of a circular ring IIE having a plurality of bars II'I affixed thereto. These bars are circumferentially spaced along the upper edge IIB of ring I|6 and are substantially perpendicular to the plane of the ring. Each of bars II'I carries on its inner surface I I9 a plurality of inwardly extending, longitudinally spaced 'projections |20. Spacing member |I5 is disposed in annular space IIA so that the outermost surface |21 of ring IIE and the outer surface |22 of bars I|'| abut against the inner surface 2 of tubular member III while projections |20 contact the outer surface II3 of sleeve H0. Thus, spacing member II5 provides support for sleeve IIB while permitting fluid to flow longitudinally in space I|4. A plurality of conduits |23 extends from tubular member III into the interior of sleeve H0. The upper end |24 of sleeve III] is closed by means of transversely extending plate I25 aixed, as at |26 by welding, to tubular member III, openings |21 being provided at the outer periphery of plate |25 to permit fluid to flow from annular space H4 into space |28 in tubular member III above plate |25. The upper end of tubular member may be swaged inwardly and provided with screw threads |29 for convenient engagement with pipe. The lower end |30 of sleeve ||0 and the lower end |3| of tubular member is closed by means of closure plate |32. It will be understood, of course, that an opening may be provided in plate |32 so that borehole fluids can flow through said opening into the interior of sleeve |||J. thel space within said sleeve between transversely extending plate |25 and closure plate |32, is filled with a highly permeable, finely divided aggregate, such as a highly permeable sand which is consolidated with a suitable material, such as plastic, to form a solid, permeable mass within said sleeve. Conduits |23 may also be filled with this permeable mass as shown.

The embodiment shown in Figs. 4 and 5 operates in exactly the same manner as the em# bodiment shown in Figs. 1 to 3, inclusive. That is to say, formation fluid enters the screen through conduits |23, as indicated by the arrows, and passes through the permeable, consolidated sand located in the interior of sleeve I0, thence through sleeve ||l into annular space ||4. The fluid entering annular space H through sleeve IIB passes upwardly in said space through openings |21 at the outer periphery |25 into space |28. Of course, the fluid in space |28 has been freed of suspended formation materials in movement through the consolidated sand and sleeve H0, this cleaned-up borehole fluid passing from space |28 through threaded end |29 in the manner indicated by the arrows.

Having fully described the invention, what is claimed as new and useful is:

l. A borehole screen for wells producing uids comprising a cylindrical, permeable filter sleeve composed of sintered metal forming an inner chamber; a nely divided, permeable consolidated aggregate filling said chamber; a tubular member surrounding said sleeve, the interior surface of said tubular member and the outer surface of said sleeve forming an annular space therebetween; spacing means disposed in said annular space for supporting said screen, said spacing means being arranged to perrriit fluid to flow longitudinally within said annular space; a transverse plate in said tubular member affixed thereto arranged to permit fluid to ow from the space between sai-d sleeve and said tubular member to the space in said tubular member above said plate; and means adapted to permit the passage of borehole fluids into said inner chamber, whereby fluids pass from the borehole through said means into the inner chamber, thence through said sleeve into the space between said sleeve and said tubular member.

2. A borehole screen for wells producing fluids comprising a cylindrical, permeable lter sleeve composed of sintered metal forming an inner chamber; a finely divided, consolidated, permeable aggregate filling said chamber; a tubular member surrounding said sleeve, an interior surface of said tubular member and the outer surface of said sleeve forming an annular space therebetween; spacing means disposed in said annular space for supporting said sleeve and spacing it away from said tubular member, said spacing means being arranged to permit fluid to flow longitudinally within said annular space; a transverse plate in said tubular member affixed thereto arranged to permit iluid to flow from said annular space to the space in said tubular The interior of sleeve H8, that is i,

member above said plate; and a plurality of conduits extending laterally through said tubular member and said sleeve into said chamber, whereby well fluids pass from the borehole through said conduits into the inner chamber, thence through said sleeve into the space between said sleeve and said tubular member.

3. A borehole screen for wells producing fluids comprising a cylindrical permeable filtering sleeve composed of sintered metal forming an inner chamber; a finely divided consolidated permeable aggregate iilling said chamber; a tubular member surrounding said sleeve, said member dening inwardly extending projections for supporting said sleeve and for spacing said sleeve from the inner surface of said tubular member, said projections being arranged to permit fluid to flow longitudinally within the space between the outer surface of said sleeve and the interior surface of said tubular member; a transverse plate in said tubular member aixed thereto arranged to permit fluid to flow from the space between said sleeve and said tubular member to the space in said tubular member` above said plate; and a plurality of conduits extending laterally through said tubular member and said sleeve into said chamber, said conduits being longitudinally and circumferentially spaced with respect to said tubular member an-d said sleeve.

\ whereby Well fluids pass from the borehole through said conduits into the inner chamber, thence through said sleeve into the space between said sleeve and said tubular member.

4. A borehole screen for `wells producing fluids comprising a cylindrical filter element having a permeable cylindrical wall composed of sintered metal and an upper end wall composed of sintered metal; a tubular member surrounding said cylindrical wall, said member defining inwardly extending projections for supporting said cylindrical wall and for spacing said cylindrical wall from the inner surface of said tubular member, said projections being arranged to permit fiuid to ow longitudinally within the space between the outer surface of said cylindrical wall and the interior surface of said tubular member; a transverse plate in said tubular member alxed thereto defining downwardly extending projections arranged to abut on the end wall of said lter element for spacing said plate from said end wall, said plate being arranged in said tubular member to permit fluid to flow from the space between said filter element and said tubular member and from the space between said transverse plate and said filter element to the space in said tubular member above said plate; a consolidated nely divided permeable aggregate lling said cylindrical lter element; and means for admitting borehole fluids into the interior of said filter element, whereby fluids pass from the borehole through said means into the interior of said filter element, thence through said filter element into said tubular member.

GUSS F. ABENDROTH.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 1,488,662 Cater Apr. 1, 1924 2,335,558 Young Nov. 30, 1943 2,359,386 Reinsch Oct. 3, 1944 

1. A BOREHOLE SCREEN FOR WELLS PRODUCING FLUIDS COMPRISING A CYLINDRICAL, PERMEABLE FILTER SLEEVE COMPOSED OF SINTERED METAL FORMING AN INNER CHAMBER; A FINELY DIVIDED, PERMEABLE CONSOLIDATED AGGREGATE FILLING SAID CHAMBER; A TUBULAR MEMBER SURROUNDING SAID SLEEVE, THE INTERIOR SURFACE OF SAID TUBULAR MEMBER AND THE OUTER SURFACE OF SAID SLEEVE FORMING AN ANNULAR SPACE THEREBETWEEN; SPACING MEANS DISPOSED IN SAID ANNULAR SPACE FOR SUPPORTING SAID SCREEN, SAID SPACING MEANS BEING ARRANGED TO PERMIT FLUID TO FLOW LONGITUDINALLY WITHIN SAID ANNULAR SPACE; A TRANSVERSE PLATE IN SAID TUBULAR MEMBER AFFIXED THERETO ARRANGED TO PERMIT FLUID TO FLOW FROM THE SPACE BETWEEN SAID SLEEVE AND SAID TUBULAR MEMBER TO THE SPACE IN SAID TUBULAR MEMBER ABOVE SAID PLATE; AND MEANS ADAPTED TO PERMIT THE PASSAGE OF BOREHOLE FLUIDS INTO SAID INNER CHAMBER, WHEREBY FLUIDS PASS FROM THE BOREHOLE THROUGH SAID MEANS INTO THE INNER CHAMBER, THENCE THROUGH SAID SLEEVE INTO THE SPACE BETWEEN SAID SLEEVE AND SAID TUBULAR MEMBER. 